The present invention relates to the field of fiber optics, and more particularly, to fiber optic devices and components.
Fiber optic systems are widely used in industries, such as telecommunications and computers. These optical systems may be more economical and more robust than copper wire systems that have been used in the past. An optical system may also make use of a fiber optic ribbon structure, such as a fiber optic ribbon cable, for example. Because of its two-dimensional nature, aligning of the fiber ends is simplified which facilitates termination procedures. Fiber optic ribbon cables may provide large fiber counts in a compact arrangement. Although fiber optic ribbon cables perform successfully in use, known fiber optic ribbon cables are not typically configured to withstand heavy mechanical loads, particularly vibration levels experienced by optical components installed within the housing of an electro-optical device as may be used in automobiles and aircraft, for example.
One example of a fiber optic cable harness for installation within a device is provided by U.S. Conec Ltd., located in Hickory, N.C. under the designation Concours(trademark) Optical Circuits. The fiber optic cable harness includes a plurality of first optical fiber connectors terminating respective first groups of first ends of optical fibers, and a plurality of second optical fiber connectors terminating respective second groups of second ends of the optical fibers.
The optical fibers may be cross-connected between the first and second connectors. The fiber optic cable harness also includes a pair of flexible Kapton(trademark) plastic layers sandwiching the optical fiber. Unfortunately, the U.S. Conec fiber optic cable harness is also susceptible to damage from heavy mechanical loads likely to occur during assembly, handling, maintenance and/or operation.
In view of the foregoing background, it is therefore an object of the present invention to provide a device including a ruggedized fiber optic cable harness.
This and other objects, features, and advantages in accordance with the present invention are provided by a device comprising a housing, a plurality of optical components within the housing, and a fiber optic cable harness connected to the optical components and extending within the housing.
The fiber optic cable harness preferably comprises a plurality of optical fibers, and a plurality of respective first and second optical fiber connectors. The first optical fiber connectors may terminate respective first groups of first ends of the optical fibers, and the second optical fiber connectors may terminate respective second groups of second ends of the optical fibers. The first and second groups may be different for defining at least one cross-connection of optical fibers between the first optical fiber connectors and the second optical fiber connectors.
The fiber optic cable harness preferably further comprises at least one optical fiber support layer carrying the optical fibers. Moreover, the fiber optic cable harness also may include a plurality of longitudinal strength members extending between the first optical fiber connectors and the second optical fiber connectors. The longitudinal strength members advantageously absorb potentially detrimental strain and/or vibration that would otherwise be imported to the optical fibers.
Each longitudinal strength member may be generally elongate and have opposing first and second ends terminated at respective ones of the first optical fiber connectors and second optical fiber connectors. Each longitudinal strength member may be flexible, and may be bendable and shape retaining.
In one embodiment of the fiber optic cable harness, each longitudinal strength member may be connected to the at least one optical fiber support layer. In another embodiment, the at least one optical fiber support layer may comprise first and second plastic layers connected together with the optical fibers and longitudinal strength members therebetween.
The optical fiber support layer may comprise generally planar portions and may have opposing first and second ends terminated at respective ones of the first optical fiber connectors and second optical fiber connectors. The support layer may also have spaced apart openings therein to facilitate securing within the housing.
The device according to the present invention may further comprise at least one first connector shell for holding the first optical fiber connectors, and at least one second connector shell for holding the second optical fiber connectors. The longitudinal strength members may extend into the first and second connector shells. The first optical fiber connectors may also be carried by the housing so as to be externally accessible.
The device may further comprise electronic circuitry connected to the optical components so that the device is an electro-optical device. The optical components may be carried by at least one circuit board within the device.
Another aspect of the present invention is directed to a method of making a fiber optic cable harness for connection to optical components within a housing of a device. The method preferably comprises terminating first groups of first ends of optical fibers at respective first optical fiber connectors, and terminating second groups of second ends of the optical fibers at respective second optical fiber connectors. The first and second groups may be different for defining at least one cross-connection of optical fibers between the first and second optical fiber connectors. The method may further include supporting the optical fibers using at least one optical fiber support layer, and connecting a plurality of longitudinal strength members to extend between the first and second optical fiber connectors.